The invention relates to a pasteurized egg-based powder whose organoleptic and functional properties are functionally similar to those of egg after reconstituting in an aqueous medium. It also relates to an egg-based fermented food of a novel type, manufactured from such a composition.
Eggs are often used for their excellent functional properties, for example their gelling and emulsifying properties, for their color and taste. It is known that egg-based food products are not free of microbiological risks since eggs may contain sporulated microorganisms and salmonella. Egg proteins usually lose their functional properties, in particular their gelling ability, under the heat treatment conditions which would be necessary for the elimination of such spores and salmonella. As is known in the art, the main problem in manufacturing dried-egg products is that the elimination of Salmonella and other bacteria requires the application of heat at high temperatures to the egg mixture during a pasteurization step, but the application of high temperatures causes the egg to coagulate. Since the coagulation process is irreversible, once the egg coagulates the egg product has lost its thickening function for other food applications.
Accordingly, industrial egg products are generally pasteurized, but this does not eliminate all risks. Because of residual risks, the use of eggs is limited. In particular, the use of eggs which have been simply pasteurized in a conventional manner under conditions which maintain their organoleptic and functional properties cannot be successfully and safely used in food products which have to undergo fermentation.
For example, U.S. Pat. No. 3,475,180 to Jones recognizes that a pasteurization step which requires temperatures above of above 148° F. (64.4° C.) to pasteurize the egg will cause the egg to coagulate. To overcome this problem, Jones proposes a reduced calorie, egg substitute in which specific amounts of yolk are removed from the egg. The removal of the egg yolk makes the egg product low-calorie since egg yolk comprises mostly fat. Also, the egg yolk protein is replaced with other selected proteins that do not coagulate during pasteurization. To overcome the lost functional properties of the egg product due to the pasteurization step, Jones teaches the addition of a thickening agent to supplement or replenish lost functional properties of the already-coagulated egg.
A spray-dried composition based on egg and skimmed milk capable of being reconstituted in water is known for example from FR-A-2 118 688. This composition results from drying a mixture of whole egg and skimmed milk which have been separately pasteurized. In particular, the egg is heat-treated at 64.5° C. for 2½ minutes, a treatment that does not make it possible to ensure complete absence of salmonella. Such a complete treatment is not necessary in the context of that document since the egg/milk powder is intended for use in cakes which are manufactured by prolonged baking of the mix at high temperature. In comparison, this composition cannot be safely used in uncooked food products, for example, dairy products.
A fermented drink based on milk and egg is also known for example from FR-A-2 737 643. Such a drink is manufactured by preparing a liquid egg mixture which has been highly diluted in water, supplemented with skimmed milk powder, glucose and fructose and a content of egg not exceeding 10% in the mixture, heat treating by pasteurization, and then cooling followed by lactic acid fermentation of the mixture thus treated. This product is not based on a powder and the egg is treated with a high temperature while being highly diluted in water.
It is also known from EP-A-0 820 704 that it is possible to sterilize a mixture of milk, egg and sugar by the liquid route and, where appropriate, drying the mixture, thereby losing the functional properties of the egg and using the gelling properties of the casein in the presence of calcium under the effect of heat to replace the functional properties of the egg which are lost during the sterilizing heat treatment. The re-established gelling properties of the system are exploited to manufacture desserts of the flan type.
The problem forming the basis of the present invention is the making available of a product based on whole egg, which would have the desired functionality, in particular the emulsifying ability and the gelling capacity, which could be used in the preparation of food products while being hygienic and in particular which would be suitable for the preparation of dairy food products. The prior art does not address this problem.
There also is a need for an easy to use texturizing powder, which has a natural image, the advantage of egg, and which is safe to use in all food products including uncooked foods. This need is now met by the present invention.